code: def observation_spec(self):
      return array_spec.ArraySpec((3, 3), np.float32)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import functools
  from absl.testing import parameterized
  import numpy
  import tensorflow
  from tf_agents.environments import batched_py_environment
  from tf_agents.environments import random_py_environment
  from tf_agents.specs import array_spec
  from tf_agents.trajectories import time_step
label_desc: Use image node_id 2 for calling the BatchedPyEnvironmentTest obj's underlying member method code with example usage: obj.observation_spec() and returns: array_spec